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A new lignan derivative from the root of Ilex pubescens

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Chinese Chemical Letters 2008年第5期19卷 550-552页

作者： Yu Bo Zhou Jin Hui Wang xiang mei li Xian li School of Traditional Chinese Materia Medica Shenyang Pharmaceutical University Shenyang 110016 China

One new compound, ilexlignan A （1）, was isolated from the root of llex pubescens. Its structure was elucidated by the combination of one- and two-dimensional NMR analysis, mass spectrometry, CD spectrum measurement ... 详细信息

关键词： llex pubescens llexlignan A lignan

Effect of short neuropeptide F signaling on larval feeding in Mythimna separata

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Insect Science 2024年第2期31卷 417-434页

作者： mei-mei li Qi Yang li-Hui Chen Yan-Ying li Jun-xiang Wu xiang-li Xu State Key Laboratory of Crop Stress Biology in Arid Areas College of Plant ProtectionNorthwest A&F UniversityYanglingShaanxi ProvinceChinaand School of Agricultural Sciences Jiangxi Agricultural UniversityNanchangChina

Mythimna separata is a notorious phytophagous pest which poses serious threats to cereal crops owing to the gluttony of the *** short neuropeptide F(sNPF)and its receptor sNPFR are involved in a diversity of physiological functions,especially in functions related to feeding in insects,it is a molecular target for pest ***,an sNPF and 2 sNPFRs were identified and cloned from *** analysis revealed that the sNPF and its receptors had a highly conserved RLRFamide C-terminus and 7 transmembrane domains,*** sNPF and its receptor genes were distributed across larval periods and tissues,but 2 receptors had distinct expression *** starvation-induced assay elucidated that sNPF and sNPFR expression levels were downregulated under food deprivation and recovered with subsequent *** interference knockdown of sNPF,sNPFR1,and sNPFR2 by injection of double-stranded RNA into larvae not only suppressed food consumption and increased body size and weight,but also led to decrease of glycogen and total lipid contents,and increase of trehalose compared with double-stranded green fluorescent protein ***,molecular docking was performed on the interaction mode between sNPFR protein and its ligand sNPF based on the 3-dimensional models constructed by AlphaFold;the results indicated that both receptors were presumably activated by the mature peptide *** results revealed that sNPF signaling played a considerably vital role in the feeding regulation of *** and represents a potential control target for this pest.

关键词： feeding regulation Mythimna separata pest control target RNA interference short neuropeptide F sNPF receptors

Using Support Vector Machine to Predict Eco-environment Burden:A Case Study of Wuhan,Hubei Province,China

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Biomedical and Environmental Sciences 2008年第1期21卷 45-52页

作者： xiang-mei li JING-XUAN ZHOU SONG-HU YUAN XIN-PING ZHOU QIANG FU School of Environmental Science and Engineering Huazhong University of Science and Technology Wuhan 430074 Hubei China China Environmental Monitoring Center Beijing 100029 China

Objective The human socio-economic development depends on the planet＇s natural capital. Humans have had a considerable impact on the earth, such as resources depression and environment deterioration. The objective of this study was to assess the impact of socio-economic development on the ecological environment of Wuhan, Hubei Province, China, during the general planning period 2006-2020. Methods Support vector machine （SVM） model was constructed to simulate the process of eco-economic system of Wuhan. Socio-economic factors of urban total ecological footprint （TEF） were selected by partial least squares （PLS） and leave-one-out cross validation （LOOCV）. Historical data of socio-economic factors as inputs, and corresponding historical data of TEF as target outputs, were presented to identify and validate the SVM model. When predicted input data after 2005 were presented to trained model as generalization sets, TEFs of 2005, 2006,…, till 2020 were simulated as output in succession. Results Up to 2020, the district would have suffered an accumulative TEF of 28.374 million gha, which was over 1.5 times that of 2004 and nearly 3 times that of 1988. The per capita EF would be up to 3.019 gha in 2020. Contusions The simulation indicated that although the increase rate of GDP would be restricted in a lower level during the general planning period, urban ecological environment burden could not respond to the socio-economic circumstances promptly. SVM provides tools for dynamic assessment of regional eco-environment. However, there still exist limitations and disadvantages in the model. We believe that the next logical step in deriving better dynamic models of ecosystem is to integrate SVM and other algorithms or technologies.

关键词： Urban eco-environment Total ecological footprint Support vector machine Partial least square

Derrisisoflavones H-K and One Isoflavan Derivative from Derris robusta

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Natural Products and Bioprospecting 2016年第2期6卷 111-116页

作者： Guo-Zhu Wei mei-Fen Mao xiang-mei li Fu-Cai Ren Fei Wang BioBioPha Co. Ltd.Kunming 650201People’s Republic of China

Four hitherto unknown prenylated isoflavonoids,named derrisisoflavones H-K(1-4)and one new isoflavan,namely 6-hydroxyisosativan(5),were isolated from the ethanol extract of Derris *** structures were elucidated on the basis of extensive spectroscopic *** our knowledge,derrisisoflavones J(3)and K(4)are the first examples of hydroxyethylated isoflavonoid.

关键词： Derris robusta Isoflavonoid Isoflavan Derrisisoflavone

Aristolane‑type Sesquiterpenoids from Nardostachys chinensis and Revised Structure of Aristolanhydride

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Natural Products and Bioprospecting 2019年第2期9卷 149-155页

作者： li-Xia Wang Xian-Jun Jiang xiang-mei li mei-Fen Mao Guo-Zhu Wei Fei Wang BioBioPha Co. Ltd.Kunming 650201People’s Republic of China Reference Substances Sub-center National Engineering Research Center for Modernization of Traditional Chinese MedicineKunming 650201People’s Republic of China

Four hitherto unknown aristolane-type sesquiterpenes,including one novel 8,9-secoaristolane,namely secoaristolenedioic acid(1),two aristolone derivatives,namely 1α,2β-dihydroxyaristolone(2),9-epidebilon(3),and one rare aristolane-chalcone hybrid,namely 3′-hydroxynardoaristolone A(4)were isolated from the ethanol extract of the roots and rhizomes of Nardostachys *** structures were elucidated on the basis of extensive spectroscopic *** addition,the structure of aristolanhydride,recently isolated from the same species,was corrected by reanalysis of the published NMR data.

关键词： Nardostachys chinensis Aristolane Secoaristolane Aristolane-chalcone hybrid Structural revision

A Weakly-Supervised Crowd Density Estimation Method Based on Two-Stage linear Feature Calibration

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IEEE/CAA Journal of Automatica Sinica 2024年第4期11卷 965-981页

作者： Yong-Chao li Rui-Sheng Jia Ying-xiang Hu Hong-mei Sun the College of Computer Science and Engineering Shandong University of Science and TechnologyQingdao 266590 the Faculty of Information Science and Engineering Ocean University of ChinaQingdao 266000China the College of Computer Science and Engineering Shandong University of Science and TechnologyQingdao 266590China the College of Computer Science and Engineering Nanjing University of Science and TechnologyNanjing 210000China

In a crowd density estimation dataset,the annotation of crowd locations is an extremely laborious task,and they are not taken into the evaluation *** this paper,we aim to reduce the annotation cost of crowd datasets,and propose a crowd density estimation method based on weakly-supervised learning,in the absence of crowd position supervision information,which directly reduces the number of crowds by using the number of pedestrians in the image as the supervised *** this purpose,we design a new training method,which exploits the correlation between global and local image features by incremental learning to train the ***,we design a parent-child network(PC-Net)focusing on the global and local image respectively,and propose a linear feature calibration structure to train the PC-Net simultaneously,and the child network learns feature transfer factors and feature bias weights,and uses the transfer factors and bias weights to linearly feature calibrate the features extracted from the Parent network,to improve the convergence of the network by using local features hidden in the crowd *** addition,we use the pyramid vision transformer as the backbone of the PC-Net to extract crowd features at different levels,and design a global-local feature loss function(L2).We combine it with a crowd counting loss(LC)to enhance the sensitivity of the network to crowd features during the training process,which effectively improves the accuracy of crowd density *** experimental results show that the PC-Net significantly reduces the gap between fullysupervised and weakly-supervised crowd density estimation,and outperforms the comparison methods on five datasets of Shanghai Tech Part A,ShanghaiTech Part B,UCF_CC_50,UCF_QNRF and JHU-CROWD++.

关键词： Crowd density estimation linear feature calibration vision transformer weakly-supervision learning

Pterocarpadiols A–D, Rare 6a,11b-Dihydroxypterocarpans from Derris robusta

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Natural Products and Bioprospecting 2015年第6期5卷 287-291页

作者： xiang-mei li mei-Fen Mao Fu-Cai Ren Xian-Jun Jiang Ping Hai Fei Wang BioBioPha Co. Ltd.Kunming 650201People’s Republic of China

Four hitherto unknown 6a,11b-dihydroxypterocarpans,namely pterocarpadiols A–D(1–4),were isolated from the ethanol extract of the twigs and leaves of Derris *** structures were elucidated on the basis of extensive spectroscopic *** A–D are a kind of very rare 6a,11b-dihydroxypterocarpans,and their presence as markers may be helpful in chemotaxonomical classification.

关键词： Derris robusta 6a,11b-Dihydroxypterocarpan Pterocarpadiol

The Non-inclusion Diagnosability of Hypercubes Under the PMC Model

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Journal of the Operations Research Society of China 2024年第2期12卷 478-484页

作者： mei-Jie Ma Min Xu Tong-Tong Ding xiang-Jun li Qiang Zhu School of Mathematics and Statistics Qilu University of Technology(Shandong Academy of Sciences)Jinan 250353ShandongChina School of Mathematical Sciences Beijing Normal UniversityLaboratory of Mathematics and Complex SystemsMinistry of EducationBeijing 100875China School of Information and Mathematics Yangtze UniversityJingzhou 434023HubeiChina School of Mathematics and Statistics XiDian UniversityXi'an 710071ShaanXiChina

Diagnosability of a multiprocessor system is an important measure of the reliability of interconnection ***-level diagnosis is a primary strategy to identify the faulty processors in a multiprocessor *** on a sound assumption proposed by Zhu et ***,we proposed a new diagnosability named non-inclusion diagnosability and showed that the non-inclusion diagnosability t_(N)(Q_(n))of the hypercube under the PMC model is *** is,assume that if two vertex sets F_(1) and F_(2) are both consistent with a syndrome and F_(1)C F_(2),then F_(2) is not the faulty set which we are looking for;the faulty set F is 1-step diagnosable if|F|≤2n-2 in Q_(n) under the PMC model.

关键词： Interconnection network Diagnosability Hypercube PMC model

Prenylated Coumarins from Heracleum stenopterum,Peucedanum praeruptorum,Clausena lansium,and Murraya paniculata

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Natural Products and Bioprospecting 2016年第5期6卷 233-237页

作者： xiang-mei li Xian-Jun Jiang Ku Yang li-Xia Wang Shi-Zhen Wen Fei Wang BioBioPha Co. Ltd.Kunming 650201People’s Republic of China

Four hitherto unknown prenylated coumarins,namely 600-O-b-D-apiofuranosylapterin(1),40-O-isobutyroylpeguangxienin(2),6-(3-methyl-2-oxobutyroyl)-7-methoxycoumarin(3),and 6-hydroxycoumurrayin(4),were isolated from the ethanol extract of Heracleum stenopterum,Peucedanum praeruptorum,Clausena lansium,and Murraya paniculata,*** chemical structures were established on the basis of extensive spectroscopic ***pound 2 exhibited in vitro cytotoxic activity against five human cancer cell lines(HL-60,A-549,SMMC-7721,MCF-7,and SW-480)with IC50 values ranging from 15.9 to 23.2μM.

关键词： Heracleum stenopterum Peucedanum praeruptorum Clausena lansium Murraya paniculata Prenylated coumarin Cytotoxicity